中文摘要：

目的：构建NOR1基因原核表达载体,并在大肠杆菌中原核表达NOR1重组蛋白,对其诱导条件进行优化,并纯化NOR1蛋白。方法：PCR扩增人NOR1基因全长开放阅读框,克隆入原核表达载体pET28b。重组质粒转化大肠杆菌,采用不同温度、不同抗生素浓度、不同IPTG浓度诱导NOR1蛋白表达。选择最佳条件大量诱导NOR1蛋白表达,采用Ni-IDE树脂纯化NOR1重组蛋白,并通过SDS-PAGE凝胶电泳检测重组蛋白的纯度。结果：成功构建了pET28b-NOR1基因原核表达载体,并转化E.coli Rosettablue（DE3）。利用IPTG诱导His-NOR1蛋白表达,结果发现IPTG浓度、温度、抗生素浓度均可影响NOR1重组蛋白的表达效率。0.25mmol/L IPTG即可诱导NOR1融合蛋白的表达,分子质量为43 kD;随着IPTG浓度提高,重组蛋白表达量增加。温度对NOR1蛋白原核表达有重要影响,低温条件（30℃）无法诱导NOR1蛋白表达。提高卡那霉素筛选浓度可以提高NOR1蛋白表达量。原核表达的NOR1重组蛋白绝大部分形成包涵体,采用6 mol/L盐酸胍溶解包涵体,通过Ni-IDE树脂纯化得到高纯度的His-NOR1重组蛋白。结论：构建了pET28b-NOR1原核表达载体。研究发现在37℃条件下,采用1 mmol/L IPTG,200μg/mL卡那霉素可以高效诱导NOR1蛋白表达。纯化得到高纯度的NOR1重组蛋白。

英文摘要：

Objective To optimize the induction condition of human NOR1 gene expression in E.coli.and purify NOR1 recombinant proteins.Methods A full-length cDNA of human NOR1 was inserted into the corresponding region of pET28b expression vector to yield recombinant prokaryotic expression vector pET28b-NOR1.The prokaryotic expression vector pET28b-NOR1 was introduced into the bacterial host E.coli Rosettablue（DE3）.Recombinant NOR1 protein was induced at different conditions.Induction condition was optimized to obtain high yield of recombinant protein.At last,the recombinant NOR1 protein was purified by Ni-IDE chromatography resin.Results Recombinant NOR1 protein was induced by IPTG in a dose-dependent manner.Increase of kanamycin concentration and induction temperature resulted in high yield of recombinant protein.The most recombinant protein was found in inclusion bodies.The recombinant His-NOR1 protein was purified with Ni-IDE chromatography resin under denature condition.Conclusion IPTG,kanamycin concentration and temperature can affect the expression of recombinant NOR1 protein in pET28b system.High yield of recombinant NOR1 protein is achieved by inducing 1 mmol/L IPTG and 200 μg/mL kanamycin at 37 ℃.Recombinant His-NOR1 protein with high purity is purified.